Game of Thrones author George RR Martin has said his impending book will go in a "somewhat different direction" than the controversial TV finale.
The 72-year-old US novelist is yet to release The Winds of Winter and A Dream of Spring, the final books in the A Song of Ice and Fire series. He says he wrote "hundreds and hundreds" of pages for The Winds of Winter last year.
The globally anticipated finale of HBO's fantasy series aired in mid-2019 to widespread disappointment, with fans accusing writers David Benioff and DB Weiss of "rushing" the eighth and final season.
In a new interview with a PBS station in Chicago, Martin expressed regret over not finishing all the books before the TV series aired its final seasons, with the show streaming locally on Foxtel.
"Looking back, I wish I'd stayed ahead of the books," Martin began.
"When they began that series, I had four books already in print, and the fifth one came out just as the series was starting in 2011.
"I had a five-book headstart. And these are gigantic books, as you know. I never thought they would catch up with me, but they did.
"They caught up with me and passed me, and, you know, that made it a little strange. Because now, the show was ahead of me, and the show was going in somewhat different directions."
The show officially passed the books toward the end of season five, which aired in 2015.
In a blog post following the show's lacklustre finale, Martin wrote: "How will it all end? I hear people asking. The same ending as the show? Different? Well … yes. And no. And yes. And no. And yes. And no. And yes.
"I am working in a very different medium than David and Dan, never forget. They had six hours for this final season. I expect these last two books of mine will fill 3000 manuscript pages between them before I'm done … And if more pages and chapters and scenes are needed, I'll add them."
He added in an interview with Fast Company: "It can be … traumatic. Because sometimes their creative vision and your creative vision don't match, and you get the famous creative differences thing — that leads to a lot of conflict," he said at the time.
"The (final) series has been … not completely faithful. Otherwise, it would have to run another five seasons.
"You get totally extraneous things like the studio or the network weighing in, and they have some particular thing that has nothing to do with story, but relates to 'Well this character has a very high Q Rating so let's give him a lot more stuff to do.'"
The GoT finale received the lowest approval ratings in the show's history, with a Rotten Tomatoes rating of 50 per cent compared to 90 per cent for all earlier seasons, with viewers mostly perplexed by the extreme and sudden downfall of Daenerys Targaryen.
Martin has previously claimed he wished for an ending similar to The Lord of the Rings.